Torsen worn out, or brg? 99 cobra IRS knuckle questions

[69fb]

I have a 99 cobra that has some OT modifications. It has a squeal in the rearend that sounded like it was coming from the rear diff. The squeal develops only after the car has been driven for about 10 miles or so. (the rear starts getting up to operating temp) There is no squeal when it's cold...in the first 10 miles. This squeal is weird...at anything under 20 mph it goes away...but anything above roughly 20-25mph and it can be heard. It's loud enough that it's audible outside of the car when driving next to barriers or buildings.

It sounds like a brg is on it's way out...but this car also has a Torsen T2...and I've read they tend to wear out prematurely...so I suppose it could be that as well.

I pulled the rear diff yesterday and took the cover off...nothing obvoius and there was not any metal seen in the fluid. WHile it's apart i'm going to replace all the brgs and and seals...and probably remove the T2 and replace it with a spare t-loc I just picked up. (unless I see a brg was definately the culprit of the noise, then i'll keep the T2) I plan on using all OEM brgs and seals for the rear diff..but while disassembling yesterday, I noticed the spherical brgs in the knuckles (top and bottom) had the boots torn. The brgs themsleves felt tight.

1.) Can I buy just new boots for the knuckle sph. brgs?
2.) If I have to buy new brgs and boots for the knuckles, should I replace with OEM or is there a good quality aftermarket brg available for rated OT use?

 

[svtguy]

1.) Can I buy just new boots for the knuckle sph. brgs?
2.) If I have to buy new brgs and boots for the knuckles, should I replace with OEM or is there a good quality aftermarket brg available for rated OT use?

#1. No. You have to buy the rear knuckle assembly to get the upper + lower bearings.

#2. http://www.maximummotorsports.com/i...e/index.php? main_page=index&cPath=21_88_359


Paul.

 

[69fb]

#1. No. You have to buy the rear knuckle assembly to get the upper + lower bearings.

#2. http://www.maximummotorsports.com/i...e/index.php? main_page=index&cPath=21_88_359


Paul.

Thanks for the info Paul....

I can't believe Ford won't sell replacement brgs since it appears to be a serviceable item. The joints themselves are good, just the dust boots are torn...i think i'll just run what I have and save the 380 bux.

 

[BlackBolt9]

I don't know why they don't offer the dust covers but I wonder if they only sell the bearings with the knuckle because the fatigue life of the bearings is longer than the aluminum knuckle.

 

[Jimmysidecarr]

Squealing rear ends are pretty unusual.

High pitched whining and low pitched howling rear ends are pretty common.

I have no ideal what could be causing a squeal unless a pinion seal came apart and is dragging on the pinion shaft.

OR

A pinion bearing seized and there is a race spinning or the bearing turning on the shaft.:shrug:

 

[ac427cobra]

I have a 99 cobra that has some OT modifications. It has a squeal in the rearend that sounded like it was coming from the rear diff. The squeal develops only after the car has been driven for about 10 miles or so. (the rear starts getting up to operating temp) There is no squeal when it's cold...in the first 10 miles. This squeal is weird...at anything under 20 mph it goes away...but anything above roughly 20-25mph and it can be heard. It's loud enough that it's audible outside of the car when driving next to barriers or buildings.

It sounds like a brg is on it's way out...but this car also has a Torsen T2...and I've read they tend to wear out prematurely...so I suppose it could be that as well.

I pulled the rear diff yesterday and took the cover off...nothing obvoius and there was not any metal seen in the fluid. WHile it's apart i'm going to replace all the brgs and and seals...and probably remove the T2 and replace it with a spare t-loc I just picked up. (unless I see a brg was definately the culprit of the noise, then i'll keep the T2) I plan on using all OEM brgs and seals for the rear diff..but while disassembling yesterday, I noticed the spherical brgs in the knuckles (top and bottom) had the boots torn. The brgs themsleves felt tight.

1.) Can I buy just new boots for the knuckle sph. brgs?
2.) If I have to buy new brgs and boots for the knuckles, should I replace with OEM or is there a good quality aftermarket brg available for rated OT use?

Torn boots on the spherical bearings is pretty common. Cooked lower boots from open tracking is common as well.

Did you check for play in your rear wheels? It could be something as simple as the halfshaft nuts coming loose. Check them and torque to 250# with a 36mm socket. (These should be checked on a REGULAR basis)


FWIW

:thumbsup::coolman::beer:

 

[69fb]

Squealing rear ends are pretty unusual.

High pitched whining and low pitched howling rear ends are pretty common.

I have no ideal what could be causing a squeal unless a pinion seal came apart and is dragging on the pinion shaft.

OR

A pinion bearing seized and there is a race spinning or the bearing turning on the shaft.:shrug:

I'm going to disassemble the third member tonight and take a look....i don't think it's a seal because they are usually noisy when cold and then quiet down when hot....opposite of what I'm experiencing.

There was no excessive play in the pinion gear when grabbing it...but I'm not throwing out a bad pinion brg either....hopefully whatever the problem is, it's obvious.

I would call this noise a high pitched whining/whirring sound. The PO told me it was from the alum diff bushings but I think he's full of $hit. I put rubber isolators in between the alum bushings with no change in sound...plus I have talked to others with the alum diff bushings and they did not experience any whining sounds after installation.

The gears feel tight...i would guesstimate backlash to be around .010 by feeling it, but i'll check tonight before I rip into it. The ring gear looks to be in perfect shape..FMS 4.10's...and there was no metal in the center section after I popped the cover off.

I appreciate the input and idea's...:beer:

 

[69fb]

Torn boots on the spherical bearings is pretty common. Cooked lower boots from open tracking is common as well.

Did you check for play in your rear wheels? It could be something as simple as the halfshaft nuts coming loose. Check them and torque to 250# with a 36mm socket. (These should be checked on a REGULAR basis)


FWIW

:thumbsup::coolman::beer:

Yes, I checked the rear wheels....no play that I could feel. I had the car up in the air and running in gear and could hear the noise was coming from the center of the car, near the third member...nothing from either side of the car. The driveshaft u-joints felt tight...

I'm going to just leave the boots go...the spherical brgs felt nice and tight...I expect they've seem some heat cycles in their time. :burnout:

Thanks for the info!

 

[Jimmysidecarr]

It kinda sounds like ring and pinion noise now. Whining and not squealing.
Though 8 to 12, I believe is a good target for lash.

4:10s with aluminum bushings will be louder and whinier than, say, 3:55s(what I have), but even a good and properly set up, set of 3:55s will have a slight high pitched white noise type of sound with the aluminum bushings.

I would check the set up and pattern on the R&P and also get a second opinion from an experienced tech.

I don't think it is possible for the T2 to be causing your symptoms, so I would retain that, since replacing clutches on the diff is no where near as easy to do, as they are in a stick axle car.

 

[69fb]

It kinda sounds like ring and pinion noise now. Whining and not squealing.
Though 8 to 12, I believe is a good target for lash.

4:10s with aluminum bushings will be louder and whinier than, say, 3:55s(what I have), but even a good and properly set up, set of 3:55s will have a slight high pitched white noise type of sound with the aluminum bushings.

I would check the set up and pattern on the R&P and also get a second opinion from an experienced tech.

I don't think it is possible for the T2 to be causing your symptoms, so I would retain that, since replacing clutches on the diff is no where near as easy to do, as they are in a stick axle car.

I just can't believe these bushings would resonate this kind of sound. It will echo off barriers and buildings when driving down the road.

I pulled the carrier last night, but wasn't able to pull the pinion since a friend is borrowing my gear puller (to remove pinion flange). The carrier bearings, axle brgs, and axle seals all seemed perfect. The ring gear looked good but the pattern was a bit wide across the teeth. The backlash measured .011" prior to disassembly. Gears are FMS.

I'd really like to keep the Torsen but i'm worried it may be the culprit of the noise.

I'll have to do some more investigating.

 

[ac427cobra]

After tearing up the OEM diff in my 2000 R in less than a few months, my Torsen T2R has been quiet as a church mouse while I have joyfully pounded the piss out of it for the last 5 years. Best damn investment I have made in a long time.

YMMV

:thumbsup::coolman::beer:

 

[Jimmysidecarr]

Any news on this???

 

[racebronco2]

I've had my tr2 in for 3 years with no problems. My 4.10's do whine a little cruising but they seem to be louder after a track day. Off the gas they make no noise, at first i thought it was the gears but the second set was just the same. When my rear spindle bearing was going out i did get some squeal when the rotor was contacting the caliper bracket.

 

[69fb]

Any news on this???

Jimmy,

I disassembled everything last night. The outer pinion brg seemed a little "dry", but felt good in the outer race. All other brgs seemed perfect. All seals seemed perfect. The contact patch on the FMS ring gear seems a little abnormal (compared to 9" ford gears anyway), with the patch going all the way across the face. I grabbed a set of Richmond 4.10's that I bought used and are supposedly good. They too, have a rather wide contact patch across the face.

Tonight i'm giving everything a final cleaning and will be assembling with OEM brgs and seals throughout, and will probably end up putting the Richmond gears back in it. If it still squeals, then the only left would've been the T2. Which probably has 30-40 events on it.

It's discouraging there isn't anything obviously wrong.....atleast to my eyes.

Any problems with Richmond 4.10's over the FMS gears? (i wouldn't hesitate in a 9" but i've heard the 8.8's are a little more "picky")

 

[ac427cobra]

Jimmy,

I disassembled everything last night. The outer pinion brg seemed a little "dry", but felt good in the outer race. All other brgs seemed perfect. All seals seemed perfect. The contact patch on the FMS ring gear seems a little abnormal (compared to 9" ford gears anyway), with the patch going all the way across the face. I grabbed a set of Richmond 4.10's that I bought used and are supposedly good. They too, have a rather wide contact patch across the face.

Tonight i'm giving everything a final cleaning and will be assembling with OEM brgs and seals throughout, and will probably end up putting the Richmond gears back in it. If it still squeals, then the only left would've been the T2. Which probably has 30-40 events on it.

It's discouraging there isn't anything obviously wrong.....atleast to my eyes.

Any problems with Richmond 4.10's over the FMS gears? (i wouldn't hesitate in a 9" but i've heard the 8.8's are a little more "picky")

You can 'cook' a Torsen on track without a diff cooler quite easily depending on how much power you have and how hard you're driving the car.

:read::idea:

 

[69fb]

You can 'cook' a Torsen on track without a diff cooler quite easily depending on how much power you have and how hard you're driving the car.

:read::idea:

I have no doubts about that....


This car came equipped with a Modine rear diff cooler setup and a custom side exhaust.

It looks like it (cooler) has been on for some-time....regardless, i'm going to be disappointed to get this thing back together only to hear that damn squeal again! :nonono:

 

[69fb]

Between waiting for parts and traveling for work...i hope to finally get everything back together this weekend. The only thing that won't be new is the torsen. If it still squeals then that was it...but i have my fingers crossed.



ON another note...when using a Torsen, should I be able to pull out halfshafts out of the rearend without removing the c-clips? (because I could) With the solid axle/trac-loc rearends you ahve to remove the clips first...wasn't sure if the torsen or IRS was different.

 

[Jimmysidecarr]

Between waiting for parts and traveling for work...i hope to finally get everything back together this weekend. The only thing that won't be new is the torsen. If it still squeals then that was it...but i have my fingers crossed.



ON another note...when using a Torsen, should I be able to pull out halfshafts out of the rearend without removing the c-clips? (because I could) With the solid axle/trac-loc rearends you ahve to remove the clips first...wasn't sure if the torsen or IRS was different.

They are spring clips on the IRS cars, since the knuckle and hub keep the axle in place laterally.
The axles come out with a very small amount of prying or should. (usually pretty easy)

 

[69fb]

What fluid is everyone running in their T2 and T2R's? Torsen's website just says to use what the factory recommends....not sure why a clutchless diff needs a friction modifier. :rollseyes:bored:

 

[ac427cobra]

What fluid is everyone running in their T2 and T2R's? Torsen's website just says to use what the factory recommends....not sure why a clutchless diff needs a friction modifier. :rollseyes:bored:

Any good synthetic fluid. Ford, Amsoil, Royal Purple etc. No friction modifier is required in a Torsen.

FWIW

:thumbsup::coolman::beer: